Papermaking machine headbox slice opening adjusting screws

ABSTRACT

A plurality of manually adjustable elongatable members structurally supported from the front wall of the conventional paper machine headbox and attached to the upper lip of the slice of the headbox, each member including a rod element having first and second abutment surfaces and axially disposed screw threads therebetween in the vicinity of the headbox front wall attachment sleeve (which also has an abutment surface). A threaded spindle element with an abutment surface at one end and a manually rotatable thimble at the other end is threaded into both the screw threads of the rod element and screw threads in the attachment sleeve. Rotating the thimble displaces the rod element to increase or decrease the slice opening, and the abutment surfaces provide mechanical stops for the upper-most and lowermost limit for movement of the rod element.

United States Patent [191 Batcher [451 Oct. 21, 1975 [54] PAPERMAKING MACHINE HEADBOX SLICE OPENING ADJUSTING SCREWS [75] Inventor: Kenneth Ray Batcher, Cumberland,

[73] Assignee: Westvaco Corporation, New York,

[22] Filed: Aug. 29, 1973 [21] Appl. No.: 392,732

[44] Published under the Trial Voluntary Protest Program on January 28, 1975 as document no.

[52] US. Cl 162/347; 33/164 B; 162/344 [51] Int. Cl. D21F 1/02 [58] Field of Search 162/347, 263, 344; 33/166, 33/167, 164 B [56] References Cited UNITED STATES PATENTS 3,463,701 8/1969 Curtis 162/347 3,575,799 4/1971 Gedemer et al. 162/347 X Primary Examiner-Robert L. Lindsay, Jr. Assistant ExaminerRichard H. Tushin Attorney, Agent, or Firm-W. Allen Marcontell; Richard L. Schmalz 5 7 ABSTRACT A plurality of manually adjustable elongatable members structurally supported from the front wall of the conventional paper machine headbox and attached to the upper lip of the slice of the headbox, each member including a rod element having first and second abutment surfaces and axially disposed screw threads therebetween in the vicinity of the headbox front wall attachment sleeve (which also has an abutment surface). A threaded spindle element with an abutment surface at one end and a manually rotatable thimble at the other end is threaded into both the screw threads of the rod element and screw threads in the attachment sleeve. Rotating the thimble displaces the rod element to increase or decrease the slice opening, and the abutment surfaces provide mechanical stops for the upper-most and lower-most limit for movement of the rod element.

5 Claims, 3 Drawing Figures US. Patent Oct.21, 1975 Sheet10f2 3,914,156

US. Patent Oct. 21, 1975 Sheet2 of2 3,914,156

PAPERMAKING MACHINE HEADBOX SLICE OPENING ADJUSTING SCREWS BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION The present invention relates to the headbox of a papermaking machine, and more particularly to a device for adjusting the slice opening of a headbox.

2. DESCRIPTION OF THE PRIOR ART In a fourdrinier machine, the paper stock is discharged from the headbox onto the forming wire through a slice opening, which controls the stock fluid flow rate, hence the absolute amount of stock being deposited on the wire at any particular time. In order to produce a web of paper having uniform thickness or caliper specifications across its entire width, the slice opening of a paper machine must be manipulated by the slice screws to account for the slice flow anomalies. The uniform caliper specifications are determined by calculating a weight profile, that is the weight or quality of paper being deposited on the wire per unit of time and unit of web width. The weight profile may be correlated to the cross-sectional area of the slice opening and the established flow characteristics of the headbox. The maintenance of the slice opening at a desired position has been a continuing problem in that papermaking industry for many years. The problems in this area, however, have been greatly amplified because of the economic demands to run more paper, per machine, per hour, and to increase the width of the paper web.

The slice opening of a paper machine consists of an upper lip and a lower lip, each extending the entire width of the headbox. The upper lip is usually in the form of a hinge supported from the front wall of the headbox. The lower lip is usually an extension in the form of an apron extending from the bottom of the headbox. The slice opening is usually positioned over the breast roll of the fourdrinier wire. The apron extending over the breast roll is usually thin, in an effort to discharge the slurry onto the wire without a drop off. Normal procedure for the papermaking technician is to adjust the upper lip, when the quantity of the stock flowing from the headbox onto the fourdrinier wire is increased or decreased. This, of course, is one of the methods by which the thickness of the paper being manufactured can be increased and still maintian the speed of the wire at its normal rate. Therefore, the adjusting mechanism must meet the maximum and minumum thicknesses of the predetermined specifications.

It should be noted at this point, that the requirements of the slice opening, as pointed out above, namely a thin apron and a width of great magnitude, render it susceptible to structural deflection, warpage, and creep.

Since the weight of the paper slurry within the headbox is supported by the base of the headbox, the weight of the paper stock at high fluid levels within the headbox will cause a structural deflection of the base plate and, hence, of the apron. Due to such deflection, the slice opening will change.

With regard to warpage, it should be appreciated that a thin flexible steel lip of feet or more is highly sensitive to temperature changes. Since the lip function and design does not permit a thermal expansion joint, dimensional changes due to temperature must be accommodated by other means.

In addition, variations in flow conditions can be compensated for by adjustments to the slice screws.

Machine age is another source of dimensional variation due to the creep phenomena. Creep is the flow of an otherwise rigid material from a high pressure area to an area of lower pressure. Steel is no exception to this general rule and as the years of stress wear on, compensation for creep must be provided. Since the magnitude of the deflection, warpage, and creep to which this disclosure is directed is of the order of a thousands of an inch (0001-0002), an apparatus of high precision is necessary to make the needed adjustments.

Therefore, it is an object of the present invention to provide a papermaking machine headbox with a device for adjusting the position of the upper lip of the slice opening which can be very precisely adjusted to any desired position.

In addition, visual inspection of the slice adjustment mechanism is desirable to evaluate the significance that prior adjustments may have on future ones as well as to develop a correlation in weight profiles. Accordingly, another object of the present invention is to provide a visual caliper indication such that a record of the lip setting at various points across the machine width may be reported by the appointed technican.

Another object of the present invention is to provide a direct relationship between the input movement of the adjusting mechanism to the output movement to the adjustment of the lip. This feature will decrease the time required to train the appointed technician to make the adjustment thereby negating, to a large extent, the requirement of cultivating a feel or skill in order to make the proper adjustment.

Still another object of the present invention is to provide positive mechanical stops for the upper-most limit and lower-most limit of the adjusting rod, so as to prevent excessive displacement or permanent damage to the slice lip and the linking pins.

SUMMARY OF THE INVENTION The present invention consists of a hand operated adjustment screw member supported from the front wall of a headbox, and attached to the upper lip of a slice of a headbox so as to provide support for the lip as well as adjustment to the lip. Such adjustment permits a relatively unskilled paper machine operator to accurately determine the needed adjustment and thereby produce a uniform paper weight profile across the width of the slice. This can be accomplished within the usual and normal variation of headbox flows, as well as variations in structural deflection, warp and creep.

A further important object of the present invention is to provide an economical stock flow control means for paper-making machinery that can be practicably applied to machine installations of conventional design.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional-side elevation of a paper machine headbox illustrating the present invention maintaining the lip of the headbox in the desired position.

FIG. 2 is a cross-section of the mechanism of the present invention illustrating the internals thereof.

FIG. 3 is a partial front view of a paper machine headbox illustrating the plurality of adjusting screws positioned so as to support the lip of the headbox.

DESCRIPTION OF PREFERRED EMBODIMENT Areaof FIG. 1 illustrates a headbox of a papermaking machine including a base.12, sidewalls 14, and

a front wall, generally indicated at 16. The lower sec- I tion of the front wall 16 connects to an inclined upper lip 21, which cooperates with a lower lip 22 projecting from the base 12 of the headbox structure. Attached to the inclined upper lip 21 is a profile bar 15. The inclined upper lip 21, in cooperation with the profile bar 15, forms a slice opening with the base structure 12 at area 24. The headbox 10 contains the dilute paper stock or slurry. The slurry is discharged from the headbox 10 through the slice opening 24 onto the fourdrinier wire 26, which passes around breast roll 28.

As previously mentioned, it is necessary to adjust the slice opening 24 for various reasons. Generally speaking, the object of maintaining the slice opening constant is to establish a stock flow of uniform density across the discharge opening of the slice. A change in the slice opening will cause a change in the stock flow rate to the fourdrinier wire, which in turn will greatly alter the relative thickness of the paper produced. Accordingly, a plurality of slice opening adjusting rod assemblies, generally indicated as 30 in FIG. 3, are respectively pivotally connected at the upper ends to support member 32, which in turn is supported to the front wall 16 of the headbox of the papermaking machine. The support means 32 runs the full width of the paper machine headbox and is structurally supported and sufficiently rigid to provide support for the adjusting assemblies of the present invention. The lower end of each adjusting assembly 30 is rotatively attached to the upper lip 21 of the slice opening, at bearing 18. The upper end of the adjusting assembly is attached to the support member 32 by sleeve ring 4. The sleeve ring 4 is rotatably attached to bearing member 35 at journal 34.

The adjusting assembly 30 consists of the rod 33 rotatively by pin 17 to bearing 18, which in turn is attached to the upper lip 21 of the headbox slice opening. The upper end of the rod 33 is provided with a reduced diameter pin portion 60 (FIG. 2) to be coaxially received within the bore of a spindle nut 6.

The spindle nut 6 and pin 60 are secured immovably together by a dowel pin 9. A second coaxial bore portion of the spindle nut 6 in the upper end thereof is internally threaded A inches-2O NF, for example), as seen at area 12, FIG. 2.

The lower end of spindle 3 is threaded at 11a so as to receive the upper threaded portion 12 of spindle nut 6. The spindle 3 has another upper threaded area 11 inches-ll NC, for example), onto which is screwed sleeve 2 at threaded area 2a. Spindle 3 is coaxially positioned with spindle nut 6 and adjusting rod 33. Likewise, sleeve 2 is coaxially positioned about spindle 3, spindle nut 6, and adjusting rod 33. Sleeve 2 is threaded at its lower extremity in area 65 so as to receive clamp nut 5. A shoulder 61 is provided on sleeve 2. The sleeve ring 4 is securely attached to the sleeve 2 between shoulder 61 and clamp nut 5. Such being the case, the combination of the sleeve 2, the sleeve ring 4, and the clamp nut 5 become a solid structure mounted to the front wall 16 of the paper machine headbox via dowel pin 34 to bearing member 35 attached to support 32 (FIG. 1).

Because of the many moving parts and the dust in the area, in which the adjusting screw will be used, a teflon seal 8 is positioned in the clamp nut 5 so as to prevent the entrance of foreign particles into the internals of the adjusting mechanisms.

Threaded areas 11 and 12 corresponding to the sleeve 2 and spindle nut 6 respectively, are coaxially positioned with adjusting rod 33. A thimble 1 is placed at the top most extremity of the spindle 3. The thimble 1 is securely mounted to spindle 3 by pin 66. The exterior of the thimble 1 is provided with hand-grip thatching as seen at area 62. As the thimble 1 is turned in a clockwise direction, the lead difference between threads 11 and 12 is such that spindle nut 6 traverses less axial movement relative to sleeve 2 than does spindle 3 and in the opposite direction.

As the thimble 1 is rotated in a counter clockwise direction, upward movement is produced in the spindle nut 6 relative to the sleeve 2 and the slice opening begins to increase. When the thimble 1 has been rotated counterclockwise to a designed number of revolutions, the spindle nut 6 at surface 67a will contact sleeve 2 at shoulder 64. At this point, no further upward movement is possible. The slice opening action of the adjustment rod 33 is at its maximum upper limit. It can be appreciated that this will protect the slice lip and profile bar from damage due to excessive opening of the slice.

Similarly, clockwise rotation of the thimble 1 ad vances the adjustment rod 33 and slice lip 21 toward the closed position. When the thimble has been rotated clockwise a select number of times, spindle 3 at surface 3a will contact the top most part 67 of adjustment rod 33. At this point, no further downward movement of the spindle nut 6 will be possible and likewise, no further downward movement of the adjustment rod 33 will be possible. The closing action of the adjustment screw 33 is at its maximum upper limit.

A differential type micrometer scaling is provided on the thimble 1 and the surface area of the sleeve 2. The scaling on the thimble 1 is engraved on the perimeter, as seen in area 63. Cooperative scaling is provided on the sleeve 2, which reads coaxially with the rod 33. A precise reading of the slice opening can be recorded. The permanently engraved scale can be calibrated to read relative differences in slice openings from zero or the actual value in inches.

It can be appreciated from the foregoing that the upper lip of the paper machine headbox 21, although made from flexible steel, has a maximum opening above which deformation of the lip will take place. By limiting the range of adjustment at any one slice screw, problems with gross permanent deformation with the slice lip and profile bar can be eliminated. Also, Because of the tendency to close the lip too much, a positive stop as to the maximum depth to which 21 can be closed is beneficial.

Since the upper lip 21 may be quite wide and may extend, i.e., for as many as 15 feet or more in width, a plurality of the adjusting rod assemblies 30 are preferably provided at closely spaced points along the upper lip 21. Since upper lip 21, made of steel, is of a flexible nature, independent adjustments may be made as required on the individual adjusting rod assemblies 30 to provide the desired stock discharge rate at various points along the width of the slice opening 24.

Consistent with my objectives, my present invention is precisely adjustable to any desired position within the maximum upper and lower limits of the slice opening. in addition, a visual indication is provided for any given adjustment which may be recorded as a matter of record for future adjustments for the slice opening.

While the invention has been described and illustrated herein by references to various specific materials, procedures and examples, it is understood that the invention is not restricted to the particular materials, combination of materials, and procedures selected for that purpose. Numerous variations of such details can be employed, as will be appreciated by those skilled in the art.

What is claimed is:

1. An apparatus for adjusting the separation distance between upper and lower slice lips of a paper machine headbox, said upper slice lip being pivotally secured to said headbox, said apparatus comprising:

a rod element pivotally secured at one end thereof to said upper slice lip for movement about an axis parallel with said upper slice lip length, the other end of said rod provided with first and second abutment surfaces and a first screw thread having a first thread lead disposed about the axis of said rod element;

an axially extended spindle element having at one end thereof an abutment surface cooperative with said first rod abutment surface and a second screw thread cooperatively engageable with said first screw thread disposed about the axis of said spindle, the other end of said spindle element provided with a third screw thread having a second thread lead disposed about said spindle axis;

a headbox mounting element having a journal element for pivotal attachment to said headbox about an axis parallel with said upper slice lip length, an

abutment surface cooperative with said second rod abutment surface and a fourth screw thread cooperative with said third screw thread; and

rotational drive means secured to said spindle element for turning said spindle element in either rotational direction about said spindle axis whereby rotation of said drive means in one direction axially displaces said rod element to increase the distance between the rod element slice lip pivot and said headbox mounting journal element and rotation of said drive means in the other direction displaces said rod element to decrease said distance.

2. Apparatus as described by claim 1 wherein said first thread lead is less than said second thread lead.

3. Apparatus as described by claim 1 comprising indicia on said drive means and said headbox mounting means, said indicia being relatively calibrated to indicate the axial displacement position of said rod element relative to said headbox mounting element.

4. Apparatus as described by claim 1 wherein engagement of said first rod abutment surface with said spindle abutment surface obstructs rotation of said spindle about the axis thereof in one direction and engagement of said second rod abutment surface with said headbox mounting element abutment surface obstructs rotation of said spindle about the axis thereof in the opposite direction.

5. Apparatus as described by claim 4 wherein engagement of said first rod and spindle abutment surfaces obstruct injurious displacement of said upper slice lip in one direction and engagement of said second rod and headbox mounting element abutment surfaces obstruct injurious displacement of said upper slice lip in the other direction. 

1. AN APPARATUS FOR ADJUSTNG THE SEPARATION DISTANCE BETWEEN UPPER AND LOWER SLICE LIPS OF A PAPER MACHINE HEADBOX, SAID UPPER SLICE LIP BEING PIVOTALLY SECURED TO SAID HEADBOX, SAID APPARATUS COMPRISING: A ROD ELEMENT PIVOTALLY SECURED AT ONE END THEREOF TO SAID UPPER SLICE LIP FOR MOVEMENT ABOUT AN AXIS PARALLEL WITH SAID UPPER SLICE LIP LENGTH, THE OTHER END OF SAID ROD PROVIDED WITH FIRST AND SECOND ABUTMENT SURFACES AND A FIRST SCREW THREAD HAVING A FIRST THREADLEAD DISPOSED ABOUT THE AXIS OF SAID ROD ELEMENT, AN AXIALLY EXTENDED SPINDLE ELEMENT HAVING AT ONE END THEREOF AN ABUTMENT SURFACE COOPERATIVE WITH SAID FIRST ROD ABUTMENT SURFACE AND A SECOND SCREW THREAD DISPOSED TIVELY ENGAGEABLE WITH SAID FIRST SCREW THREAD DISPOSED ABOUT THE AXIS OF SAID SPINDLE THE OTHER END OF SAID SPINDLE ELEMENT PROVIDED WITH A THIRD SCREW THREAD HAVING A SECOND THREAD LEAD DISPOSED ABOUT SAID SPINDLE AXIS, AHEAD BOX MOUNTING ELEMENT HAVING A JOURNAL ELEMENT FOR PIVOTAL ATTACHMENT TO SAID HEADBOX ABOUT AN AXIS PARALLEL WITH SAID UPPER SLICE LIP LENGTH, AN ABUTMENT SURFACE COOPERATIVE WITH SAID SECOND ROD ABUTMENT SURFACE AND A FOURTH SCREW THREAD COOPERATIVE WITH SAID THIRD SCREW THREAD, AND ROTATIONAL DRIVE MEANS SECURED TO SAID SPINDLE ELEMENT FOR TURNING SAID SPINDLE ELEMENT IN EITHER ROTATIONAL DIRECTION ABOUT SAID SPINDLE AXIS WHEREBY ROTATION OF SAID DRIVE MEANS IN ONE DIRECTION AXIALLY DISPLACE SAID ROD ELEMENT TO INCREASE THE DISTANCE BETWEEN THEROD ELEMENT SLICE LIP PIVOT AND SAID HEADBOX MOUNTING JOURNAL ELEMENT AND ROTATION OF SAID DRIVE MEANS IN THE OTHER DIRECTION DISPLACES SAID ROD ELEMENT TO DECREASE SAID DISTANCE.
 2. Apparatus as described by claim 1 wherein said first thread lead is less than said second thread lead.
 3. Apparatus as described by claim 1 comprising indicia on said drive means and said headbox mounting means, said indicia being relatively calibrated to indicate the axial displacement position of said rod element relative to said headbox mounting element.
 4. Apparatus as described by claim 1 wherein engagement of said first rod abutment surface with said spindle abutment surface obstructs rotation of said spindle about the axis thereof in one direction and engagement of said second rod abutment surface with said headbox mounting element abutment surface obstructs rotation of said spindle about the axis thereof in the opposite direction.
 5. Apparatus as described by claim 4 wherein engagement of said first rod and spindle abutment surfaces obstruct injurious displacement of said upper slice lip in one direction and engagement of said second rod and headbox mounting element abutment surfaces obstruct injurious displacement of said upper slice lip in the other direction. 